It has been known in the art of multiple hydraulic connection to provide series of multiple port valves in order to effect desired fluid communication paths for many purposes. For example, since it is generally required to provide various fluid communication paths in order to measure pressure, calibrate equipment and clean and purge hydraulic systems, multi-port valves can be used which combine fluid connection and blockage of multiple hydraulic communication ports. In the case of medical applications, hydraulic connections can be particularly critical especially since hydraulic lines can be in direct communication with human fluid conduits such as vessels, arteries, etc. Thus, a failure of a hydraulic system could result in severe damage to the patient.
Furthermore, in the art of medical care it has been known to provide a computer controlled medical care system in which automatic or manual control of a variety of medical procedures including diagnostic procedures can be carried out. Thus, in U.S. Pat. No. 4,464,172 to Lichtenstein, it is known to perform a number of procedures such as infusion of physiologic fluids, monitoring of hemodialysis, ultrafiltration, hemofiltration, medical drainage and irrigation procedures, etc. This system is designed basically to monitor, by use of sensors, the flow to or from the body and to generate command signals necessary to either stop, start, or otherwise modify the flow into or out of the body and/or effect analysis of such fluid.
In U.S. Pat. No. 4,112,272 to Jonsson et al. a measuring device is disclosed which transmits signals to a device having an electro-mechanical switch and valve mechanism for switching off to automatic zero balance and automatically calibrate. This disclosure shows the manipulation of an instrument responsive to flow in and out of a body wherein a signal is generated to a control unit.
While these devices, as well as others, may prove adequate with regard to flow directly into and out of a body, they are inadequate for operation of a multifunction fluid communication system which requires simultaneous and/or step-wise control of multi-port control valves connecting various fluid sources, reservoirs, instruments, and fluid-effecting environments.
There has been, however, a need for a multifunction fluid communication control system in the medical field, especially in an area of catheterization processes and systems. In a cardiac catheterization procedure, a flexible plastic tube is positioned in the heart to perform various diagnostic tests, and several fluid communication paths must be continuously established in order to perform the many tasks associated with making a proper diagnosis. For example, not only do the doctor and attending technicians have to be able to continuously monitor pressure within the cardiac chambers, but the system must continuously or periodically be flushed to remove blockages and clotting, as well as periodic calibration be performed on the pressure measuring instrumentation in order to achieve accurate readings.
Other procedures not associated with catheterization also require a multi-function fluid communication control system to combine operations such as infusion, flushing, pressure measurement, dye injection, blood extraction, etc., which require simultaneous and step-wise control of various fluid and pressure conditions.
In my U.S. Pat. No. 4,819,653, the subject matter of which is incorporated herein by reference, there is disclosed a multi-function, fluid communication control system for simultaneous and stepwise connection of fluid communication between ports of hydraulically connected multi-port fluid communication valves. That control system solved many of the drawbacks associated with the prior art devices.